1. Field of the Invention
The present invention relates to an extruded netting for use in erosion control net, mulch stabilization, and turf reinforcement which can be useful in reducing potential for animal entrapment and/or enhancing soil stabilization.
2. Background Art
The continuous extrusion of plastic netting started in the 1950s. Extruded netting is netting in which the strands are extruded from a die, the joints therebetween being formed either within the die or immediately outside the die. A variety of configurations are known, such as square, diamond, twill, etc. Some of the more common materials used to prepare extruded netting are polypropylene, polyethylene (particularly linear low grades, and ethylene copolymers), nylon, polybutylene, and blends thereof.
Currently, the extrusion process of choice for manufacturing plastic nets is one in which individual plastic strands are extruded in an interconnecting network to provide the net-like structure. Typically, either a rotary or a reciprocating extrusion process is employed. Methods for practicing the reciprocating technique are well known. For instance, U.S. Pat. Nos. 3,700,521; 3,767,353; 3,723,218; 4,123,491; 4,152,479 and 4,190,692 show apparatus and methods for making nets by the continuous extrusion of individual plastic strands. The disclosures of the above-mentioned issued patents are incorporated by reference into the present application.
Plastic netting has found a number of uses in commerce. For example, these nets have found use as breathable packaging netting for produce and other perishable items, agricultural netting, such as bird and hail guard netting, and netting for industrial, filtration, and home furnishings applications.
Netting has also found use in certain composites. In such composites the netting is laminated or otherwise combined with one or more fabric overlays. Chief among such uses and composites are fabrics for disposable diapers, incontinent briefs, training pants, bandages, dressings, diaper holders and liners, feminine hygiene garments, medical gowns, medical drapes, mattress pads, blankets, sheets, clothing, consumer wipes and other like products, such as building and construction composites.
One specific use of plastic netting is to serve as at least one of the outer layers or a structural support for erosion control applications, such as erosion control blankets. Erosion control blankets are well known and are used to inhibit soil degradation and erosion due to water-runoff in surface areas prone to such environmental destruction such as highway embankments, water drainage ditches, channels, and landscaping.
Another use for the plastic netting is to serve as mulch control netting. These nettings are rolled out over the top of a seeded or mulched area and are staked into place in order to keep the mulch or seed into place, providing erosion control protection under the applied treatment. Typical mulch materials include straw and hay. This type of application is used where the mulch material may benefit from external stabilization, but does not demand the superior protection that is obtained through the use of an erosion control blanket.
Yet another use for the plastic netting is to serve as turf reinforcement either in the form of a field net or a turf wrap. Field net is a durable mesh that is laid down on a seedbed usually prior to or just after seeding to facilitate grass root consolidation. The netting helps allow the grass seedlings to germinate and grow while the roots intertwine with the mesh to create a reinforced uniform structure. Because of the stronger system, growers can usually harvest earlier with generally thinner slabs maximizing land utilization. Turf wrap is applied during harvest to reinforce large rolls of turf. The rolls are wrapped to protect the turf during harvest, transportation and installation to minimize turf loss and maintain roll quality. Turf wrap can remain on the rolls or be removed during installation based on customer needs.
There are many varieties of erosion control blankets that are used today. One such variety comprises two opposed netting materials, such as plastic netting, which sandwiches a loose fibrous material. Such loose fibrous materials are well known and can comprise natural fills such as straw, coconut, coir, wood fiber and excelsior as well as synthetic types of fills such as materials made of polyethylene, polypropylene, polyester, polyvinylchloride, and nylon fibers. Another type of erosion control blanket comprises a loose fibrous fill material having a netting material embedded therein.
One drawback that has been discovered in using netting in erosion control assemblies, such as erosion control blankets and as a mulch control net, is that small animals such as snakes, lizards, and frogs tend to get stuck in the netting openings as they try to weave through the openings. When these animals become trapped, they can cause harm to the erosion control assembly and/or to themselves. For instance, the animals can damage the erosion control assembly and/or dislodge the erosion control assembly from its desired location while trying to dislodge themselves from the netting. Moreover, the animal could perish while trapped in the netting either by not being able to get to food and/or water or by being easy prey for other animals.
Accordingly, it would be advantageous to provide a netting for use in an erosion control blanket and other like erosion control applications, such as mulch control, that would help reduce the incidents of trapped animals in the netting.